Remote Sensing (RS)
Mohamad Fathollahzadeh; Mojtaba Yamani; Abolghasem Goorabi; Mehran Maghsoudi; Mernoosh Ghadimi
Abstract
Extended Abstract
Introduction:
The landforms created by tectonic processes are studied by morphotectonics, in other words, morphotectonics is the science of applying geomorphic principles in solving tectonic problems. Quantitative landscape measurements are usually based on the calculation of geomorphic ...
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Extended Abstract
Introduction:
The landforms created by tectonic processes are studied by morphotectonics, in other words, morphotectonics is the science of applying geomorphic principles in solving tectonic problems. Quantitative landscape measurements are usually based on the calculation of geomorphic indices, using topographic maps, satellite images aerial photographs, and field visits. Coastal deltas are part of landforms and landscapes that, due to the proximity of two environments, land, and water, leave visible effects against tectonic activities, such as changing the pattern and location of deltas due to the change in the course of coastal rivers, the formation of unbalanced coastal terraces in parts of the coast, and the emergence of cut beaches in the form of seawalls.
One of the methods of identifying and measuring land changes is using radar remote sensing. The principles of this technique were first described by Graham in 1974 (Pacheco et al., 2006). Interferometry using radar images with an artificial window or SAR is a precise method based on the use of at least two radar images of the same area, which measures the height displacement changes in wide areas and during different time intervals with a significant accuracy of millimeters (Dong et al., 2018).
The coastal areas of northern Iran are of great importance due to the high population density and the ability to grow and develop economically and agriculturally, so monitoring geomorphic changes in the direction of sustainable development of these areas is particularly important.
In this research, the eastern coast of the Caspian Sea from Gomishan to Joibar is investigated in terms of subsidence and uplift using radar remote sensing techniques to determine the active tectonic zones of the coast in terms of temporal and spatial changes.
Materials and Methods:
The Eastern Caspian Plain is the border between the Caspian Sea and West Gorgan and includes the cities of Gomishan, Bandare Turkman, Bandare Gaz, Gulugah, Khazarabad, and Joybar. The absolute height of the Caspian Plain along the coastline is determined according to the sea level, based on the hydrographic data of the Baku station, since 1850, the Caspian sea level has varied between -25.4 and -29.4 (Abdolhi Kakrodi, 2012).
The history of seismic activity in North Alborz shows that cities like Rasht, Lahijan, Amol, and Gorgan, have been destroyed many times due to destructive earthquakes (Aqhanbati, 2013). The Alborz fault is an active fault that is stretched in a clockwise direction in the southern Caspian basin.
In this research, according to the desired goals and radar remote sensing techniques, a series of Sentinel-1 radar images with a suitable time and space difference (maximum 30 days and maximum 150 meters respectively) including 61 images in time from 2014 to 2021 were prepared and processed.
Results:
The results obtained from the SBAS model indicate that the eastern part of the Caspian coast is more affected by the uplift and this trend continues up to Gorgan Bay. The Gorgan city has an uplift between 20 and 40 mm/year, which is reversed towards the coastal area, and subsidence of 10 to 52 mm/year occurs, which decreases as it approaches the coast and reaches 10 mm /year.
Discussion, Conclusion:
According to the results obtained from radar interferometry, the eastern coast of the Caspian Sea is more affected by uplifting. The Gorgan city has an uplift between 20 and 40 mm/year, which is reversed towards the coastal area, and subsidence of 10 to 52 mm/year occurs, which decreases as it approaches the coast and reaches 10 mm/year.
To verify the results obtained, the data of the Gorgan geodynamic station was used, which shows subsidence of about 90 to 100 mm in a 6-year period, which is consistent with the values obtained from radar interferometry Based on comments Shahpasandzadeh (2013) and the reports of Nazari et al (2021), active tectonics caused by the Caspian fault that indicates the horizontal geodynamic displacement diagram of Gorgan, the small area towards the north and east during this time, which is observed in the form of numerous branches with a thrust (reverse) mechanism and a right-slip component with a slope to the south in Golestan province.
Considering that the main feature of the coast of the Caspian Sea is the Surface rivers and the use of groundwater is very little and also the extraction of gas, oil, and mining resources, which is another factor in the occurrence of land subsidence, does not exist in this area, and there isn’t also huge and heavy structure in the study area that affects the subsidence of the surface; so displacement in the study area is the result of active tectonics.
Mojtaba Yamani; Arefeh Shabanieraghi; Seyed Mohammad Zamanzadeh; Abolghasem Goorabi; Nafiseh Ashtari
Abstract
Extended Abstract
Introduction
Climate changesare considered to be the most important event of the Quaternary period largely reflected in the geomorphology and sedimentology of the period.Paleogeomorphology helps us to understand past climate changes and predict future changes. Depending on the ...
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Extended Abstract
Introduction
Climate changesare considered to be the most important event of the Quaternary period largely reflected in the geomorphology and sedimentology of the period.Paleogeomorphology helps us to understand past climate changes and predict future changes. Depending on the Quaternary periods, closed pitlakes are called cold or rainy period lakes.Some of these lakes have completely dried up, others are temporary lakes that change into playas in the dry season, and others have been larger in the past. Researchers can identify pluvial lakes in today’s arid regions, because of the variety of factors and complex processes involved in their formation.Mighan Playa is located in the central and southwestern areas of Markazi province. It includes seasonal and saline Tozlogol Lake, and alluvial plains.
Methodology
The present study used evidences of playa lake sediments as well as geomorphological evidences(lake terrace) to investigate the extent of MighanLake in Quaternary period. Data included datacollectedfrom library sources, statistical data, field surveys, sedimentary samples, sedimentary evidences, climatic data, remote sensing data received from Landsat TM satellite, ETM, and SRTM digital elevation models(SRTM 90 meters, and Dem10 meters).Initially, previous studies and environmental characteristics of the area were analyzed. Then, lake terracewas investigated to find geomorphic evidences of Pluvial Lakes in Quaternary period. To do so, probable ranges of the lake Terrace were determined using satellite imagery, geological maps, and elevation data of digital models. Probable area was divided into several distinct zones, and finally an area was identified in the western part of the lake and based on the elevation of this zone, the extent of the lake catchment in Quaternary period was determined. During fieldwork, samples were collected from the mountain slope line toward the Playa and lake shore, and then granulometrytests were performed on the 14 collected samples to determine the amount and type of sediments.Sedimentary and graphical analysis were also performed based on Folk classification. The percentage of clay and sand in the new samples collected from the region containing this mountainous area, lake coast and deeper parts of the lake were determined and attributed to past sediments. In this way, the information could be used to determine the extension of lake sedimentsin the past.Based on sedimentary logs (Arak Groundwater Studies Report, Central Water department of Markzani Province), sedimentology studies and percentages (clay-sand-gravel) of present-day samples collected from deep sections of Playa andelevated areas of sediment pits were interpolated in GIS environment and a map of the lake extension in the Mighan catchment areawas prepared.Subsequently based onpaleogeographic studies, paleontological climate of the area and sedimentation rate calculated by Pedrami in 1993, a map was produced to show the extent of sediments and the lake progressions and regressions in the past.
Discussion
The stratigraphic and sedimentary evidences of logs in the margins of Mighanpit indicates changes in wet and dry periods. Type and size of sediments reflect the climatic conditions in each period, while high percentage of clay sediments reflects lake conditions. Paleontological sedimentological maps of the area show that the clay sediments were more concentrated in the southwestern, western and northwestern regions. Uplift of the Talkhab fault in the northeastern regionhas resulted in tectonic asymmetry of the pitand concentration of sediments in the western and southern parts. According to Krinsley, Bubeck, Pedrami and etc. Lake Mighan has been larger in the past. However, none of these researchers have determined the extent of lake water in the past. In this study, the extent of the lake was determined by reconstruction of clay sediments and using geomorphological evidencescollected from the lake shorelines (lake terrace) near Mighan village (Mashhad). Results indicated a height of 15 m in Quaternary period.
Conclusion
Sedimentary and geomorphologic evidences indicated that compared to the present playa level, the Lake fluvial was more permanent and vast in the past, but this extension differs in different directions and shows significant differences due to the tectonic location of the area.
Mojtaba Yamani; Fatemeh Yusefi; Anvar Moradi; Musa Abbasi; mohsen barzkar
Abstract
Abstract[1]
In this research, 10 variables of elevation, slope, slope direction, soil, lithology, land cover, communication roads, fault, flood potential and landslide potential have been used in order to plan land use for tourism development with multi-factor evaluation approach for the study area.
In ...
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Abstract[1]
In this research, 10 variables of elevation, slope, slope direction, soil, lithology, land cover, communication roads, fault, flood potential and landslide potential have been used in order to plan land use for tourism development with multi-factor evaluation approach for the study area.
In this research, different maps with different scales, ARC GIS10 software, and ‘Super Decisions’ software were used. In the next step, variables were evaluated using ANP and AHP models and according to experts’ opinions. Then, using the spatial analyzers in the GIS environment, the outputs were derived from the reference maps, and while overlapping these maps in GIS environment using algebraic sum operator, the final output was obtained as land use zoning for spatial zonation of tourism.The results were calculated in three qualitative classes, forbidden, contingent and permitted, and showed that about 21% of the region is eligible for development of tourism and about 42% of the region has the potential to develop only conditionally with the ecological aspects observation. About 37% of the region shows the prohibition of tourism development as well. In areas that are permitted for tourism development, in case of favorableuse and provision of facilities and welfare services and appropriate promotion, their potential can be used to develop sustainable tourism and to establish the economic balance of different regions especially in underdeveloped and rural areas. The results of this research can be used as an index for the development of appropriate and optimal applications within the framework of economic plans in the region.
[1] - به دلیل کیفیت نامناسب متن چکیده مبسوط انگلیسیِ ارائه شده توسط نویسنده مسئول مقاله، نشریه به ناچار اقدام به ترجمه مجدد متن چکیده فارسی و انتشار آن به جای چکیده مبسوط انگلیسی نموده است.
Mojtaba Yamani; Shahnaz Alizadeh
Abstract
Landfill location is one of the most important aspects of municipal solid waste management. Geomorphology is of great importance in optimal location due to its nature, which relates to the origin and development of landforms and their formation processes. Hashtgerd region with an area of 398 km2 is located ...
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Landfill location is one of the most important aspects of municipal solid waste management. Geomorphology is of great importance in optimal location due to its nature, which relates to the origin and development of landforms and their formation processes. Hashtgerd region with an area of 398 km2 is located south of Savojbolagh city of Alborz province. Due to its location on the alluvial cones of permanent rivers (Kordan) and high permeability of lands, the presense of surface water and groundwater layers sometimes at a low depth (less than 50 meters), population areas (urban and rural) and abundant agricultural lands, optimal landfill location in this area in a way that does not damage the surrounding environment is of great importance and necessity.The purpose of this research is optimal location of landfill in Hashtgerd area using AHP method and considering the geomorphologic parameters. The research method is analytical-comparative method. In this research, topographic maps of 1:25000 and geological maps of 1: 100000, as well as data related to groundwater in the study area were used and ArcGIS software was also used for analysis. In the present article, based on four main criteria, namely geology, hydrology, topology and land use, five areas were obtained for locating the landfill. The result of the research shows that the areas are perfectly suitable for landfill in the eastern and southern parts of the area around Mohammad Abad Afshar village and the areas in the western parts of the region are entirely inappropriate for landfill because of the location of population and agricultural areas and the groundwater low depth (7 to 32 m) in this part of the region.
Siavosh Shayan; Gholamreza Zare; Mojtaba Yamani; Mohammad Sharifikia; Mohsen Soltanpour
Abstract
Meanders are one of the typical geomorphological forms that is frequently observed on the southern coasts of Irandue to the availability of environmental conditions. These dynamic and active landforms have strong spatial variations under the influence of the dynamics of the rivers and the ...
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Meanders are one of the typical geomorphological forms that is frequently observed on the southern coasts of Irandue to the availability of environmental conditions. These dynamic and active landforms have strong spatial variations under the influence of the dynamics of the rivers and the gentle slopes of the deltas, in a short period of time. It’s been tried in this paper to extract and analyze the morphological changes of the Mond River bed over a period of 57 years in five time periods of (1955, 1985, 1994,
2000, and 2012) using remote sensing data and field surveys. The results of this research showed that the morphological changes of the Mond river bed have been very high during the years 1955 to 2012, so that, a nearly 3.5 kilometer displacement of the bed was observed on the estuary. Spatial comparison of the river bed in 1955 and 2012 indicated that 42.52 square kilometers were added to the left bank of the river, while on the right riverside, this amount was calculated to be 33.8 km2.The gentle slope of the delta (reduction of water speed and the sedimentary deposition on the river bed), vegetation cover on the riverside and on the river bed (trapping sediments in the river bed) and humans (building dams on the Mond river basin, constructing bridges and protection platforms on the bottom of the river bed and the transferring of water to the shrimp breeding sites) are among the important factors in changing the Mond river bed.
Hossein Kalantari Khalilabad; Ahmad Pourahmad; Mojtaba Yamani; Mohammadtaghi Rahnamaei
Volume 17, Issue 68 , February 2008, , Pages 57-61
Abstract
Natural disasters and accidents are a global problem and, in particular, one of the major issues affecting countries especially Iran, which has been raised in international affairs and humanitarian associations as a global problem and common pain among people, and have been considered in in countries’ ...
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Natural disasters and accidents are a global problem and, in particular, one of the major issues affecting countries especially Iran, which has been raised in international affairs and humanitarian associations as a global problem and common pain among people, and have been considered in in countries’ major policy making as an important social, economic, security and political issue. Whatever the country can act more efficiently and powerfully in controlling destructive phenomena effective in economic and social disruptions, and in minimizing the damage caused by their occurrence, it will have helped the economic, welfare and security strength of the country. Therefore, in this regard, and with the hope that a small step will be taken in the definition of sand storm management, this article aims to define and describe a series of terms related to sand storms and relevant issues, and by doing so, it will help coordination, completion and coherence of actions.
Mojtaba Yamani
Volume 14, Issue 53 , May 2005, , Pages 30-34
Abstract
So far, geomorphology has not found its true status in environmental studies as an applied science. Perhaps one of the most important reasons for this issue is lack of sufficient knowledge of users and managers about this branch of environmental sciences. Geomorphologic studies are not of long history ...
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So far, geomorphology has not found its true status in environmental studies as an applied science. Perhaps one of the most important reasons for this issue is lack of sufficient knowledge of users and managers about this branch of environmental sciences. Geomorphologic studies are not of long history on the international level, but nevertheless they have been widely used in many European and American countries due to their applications as well as practical necessities. In this regard, practical geomorphologic maps are considered as the most important tool for geomorphological studies. Since geomorphologic phenomena are highly complex and varied, the information on these maps are diverse and complex as well. Obviously, the ability to use these maps is equally dependent on the skill and knowledge of its suppliers and users. In general, the information on detailed geomorphological maps is divided into 4 general groups. This group of information can be emphasized according to the goals and fields of study, and become thematic. In addition, the scale of maps is also a determining factor in the possibility to display details. Therefore, in order to prepare a geomorphologic map from each region, there is first a need for sufficient scientific background and then knowledge of the goals, details and necessity of geomorphological studies.
